Causes
PID is caused by a bacterial infection in parts of the upper reproductive tract. The most commonly affected organs include the fallopian tubes, ovaries, and uterus. The bacteria most commonly associated with PID are Neisseria gonorrheae and Chlamydia trachomatis, but bacteria normally present in the vagina and cervix may also be involved. The cervix produces mucus that normally prevents bacteria from spreading to the upper reproductive tract. Researchers believe that the bacteria migrate upwards when this normal body defense is not working at its strongest (i.e., during ovulation and menses).
Risk factors for PID include:
- number of sexual partners (the more partners, the greater the risk)
- being sexually active before age 25 (women)
- current or past STDs
- douching more than once or twice a month
- use of intrauterine device (IUD) contraception - it may slightly increase the risk of PID (this risk is lowered when women are tested and treated for infections before getting an IUD)